Portable scaffold.



J. A. GRANGER. PORTIABLE SCAFFOLD. APPLICATION men NOV. 29, 1912.

1,136,898. Patented Apr. 20, 1915.

v 2 SHEETS-SHEET 1. 69 2' 26 f Y W @n/V 5 r J v J. A. GRANGER.

PORTABLE SCAFFOLD.

' APPLICATION FILED NOV. 29, 1912.

1,136,898. Patented Ap1n20, 1915.

2 SHEETS-SHEBT 2.

- iwisnza" Q. FW/7% 62. 5362719127 name snares Jenna GRANGER, orCHICAGO,

PATENT omen;

ILLINOIS, ASSIGNOR 0F ONE HALF T0 MACOMBER &

WHYTE ROPE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

romABLn scAFroLn.

Specihcation of Letters Patent.

Patented Apr. 20, 1915.

Application filed November 29, 1912. Serial No. 733,989.

To all whom it may concern:

Be. it known that 1, JOHN A. GRANGER, a

citizen of the United States, residing at Chicago, in the county of Cookand .State of lllinois have invented new and useful I Inprovements inPortable scaffolds, of whlch the following is a full, clear, and exactdescription. j I

My invention relates especially to scaffolds used by builders whenconstructing and .erecting building structures, which can .be

knocked-down when not in use, and readily transported from place toplace and erected for use whenever and wherever de; sired. f

The objects of my invention are, first, to

make" the scafiold safer to use, and more the Outriggers from which saidplatform is suspended as the height of the building 1sincreased. This, Iaccomplish malnly through the instrumentalities of guidecables to whichsaid platform is anchored and supported'in any suitable position whichit may occupy while said outriggers are being changed, and by othermeans substantiallyas hereinafter fully described and as moreparticularly pointed out 111 the claims, reference bein had to theaccompanying drawings formmg a part hereof, in which,

Figure 1 is sectional elevation of my portable scaffold installed in thefront Wall of a building under construction.- Fig; 2 is a frontelevation of one end of the same. 3 is atop plan view of one end of thescaffold platform.' Fig, 4: is an enlarged frontelevation of the hoistimdrum and the related parts of saidsscafi'ol Fig. 5 is a.

brackets detached from the platform.

Referring to the drawings, 1 represents the metal skeleton of a modernbuilding,,

and 2 is the masonry wall for one side thereof that is only partiallycompleted. Secured preferably flat to the roof or on top ofthis'skeleton, in such manner that one end thereof projects beyond theroof and overhangs the front of the building, are the beams 3 of asuitable outrigger device.

two or more of these There are preferably outrigger beams arranged asuitable distance apart, and they have concave sheaves or pulleys 7mounted on their ends over which suitable suspending ropes or cables 8travel. The lower ends ofthe outer stretches of these cables 8, arepreferably secured to the outer edge of the platform of my im provedscaffold, and the lower end of the inner stretch of said cable issecured to and wound upon the drum ofa suitable winch,

as will'hereinafter be more fully de 'cribed.

The platform or floor of the sea prises a sufli'cient number of ,j lanks or boards, whose ends rest upon and are secured to metal'sills orcross-members 10, the inner ends of which latter are see red to thecenters of length of metal uprig ts 9, and the outer ends .of which aresecured to and 1d comsupported by angular struts or braces 12,

the lower ends of which preferablp, to the lower ends ofv said uprights.e outer ends of'the sills 10 have suitable posts 14 secured thereto and,arising therefrom a suitable distance, and a fence or guard-rail 15consisting of suitable wire netting or other fencing or railingstructure, extends between and has its ends secured to said posts. Thesills 10 adjacent these posts latter are secured,

are provided with means to which thelower ends of the outer stretches ofthe hoisting or suspension-cables 8. are secured, and from thence saidcables extend to and around sheaves 7 and then down to the hoisting.winches mounted on the platform of the scaffold adjacent uprights9.

The winches just mentioned comprise a suitable winding drum l7 and theshafts upon which said. drums are mounted are preferably arranged atright angles to the front of the building, and have their outer endsjournale'd suitable bearings secured to standards 9*, that are securedto and arise from sills 10, and hhve theirnpper ends tied to theuprights 9 both by horizontal tie-bars 9 and by inclined struts 9. Theouter ends of drums 17 have a gear 15 secured thereto,- which is,preferably, greater in diameter than the flanged ends of the drum and isengaged by a pinion mounted on the adjzfcent end of a spindle 19 journaled in suitable bearings located above thebearings of thedrum-shaft, and turned by means of a crank on the outer extended endthereof.

Any kind of a pinion might be used on the spindle l9't6 transmit themotion thereof to the gear 18,-but-I prefer to construct this pinion sothat it will hold said gear and drum in any position to which they maybe turned. I have, therefore, constructed this pinion of two transverseplates 21, 2i, the former of which is secured directly to the spindle,and the latter of which is separated therefrom by pins 23 that are castin one piece with said plates. The pins 23 are parallel to the axis ofthe pinion and are located an equal distance therefromoppo; site eachother. The distance between these pins enables the pinion to engage theteeth of the gear 18, and the tendency of the drum and gear to reversewill cause the teeth of the gear to press against the pins of the pinionin a line practically intersecting the axis of the opinion and of thepins thereof, and when at rest said pinion pins will directly oppose thereverse movement of the gear. At the same time, this opposition will not"prevent the operation of the winch, by manual efforts, when it isdesired to revolve the same in either direction. The ends of the drumsopposite gears 18 are each provided with a suitable ratchet 25, that isengaged by a pawl 26 pivotally connected to uprights 9 that prevent thereverse movement of the drum when the same is at rest.

In order to prevent movement of the platform to or from the building, orhorizontally parallel with the adjacent wall thereof, I have providedguide-cables 27, which, although having a certain amount of flexibility,are retained very taut by having their upper ends secured to hangers 28secured to the top of the building, preferably, above the plane of thebeam 3, in such manner that the ends thereof to which said guide-cablesare attached overhang the front of the building. The lower end of saidcables 27 are sec'uredto the outwardly projecting'ends of brackets 29that are secured to the structure of the building, preferably, near thefoundation thereof, or, if this, IS inconvenient, at some point belowthe position of the platform of the scaffold. The uprights 9 of theyscafl'old at or near both their upper and lower ends are provided withguides through which cables 27 pass, and these guides comprise parallelplates 30 whose ends farthest y from the wall are secured to theuprights 9, in any suitable manner, and whoseoppositc edges haverearwardl projecting arms 31, between which suitab e wheels 32 arejournaled in such manner that said wheels come 1 in: contact with androll against the wall of the" building. Cables 27 extend down betweensaid'plates 30 at suitable-points near uprights 9, and are directed intheir movements by concave sheaves or rollers 33. At

. secured to t are engaged by the serrate eccentric perphcry of jaws 35,the trunnions of which are journaled in suitable bearings in plates 30and have handles 36 that pass forward through openings in the web'of thean leiron uprights 9 at a suitable point, pre erably, above the drum,within convenient reach of the operator without interferring with themanipulation of the winch.

It will be understood that structural changes may be made in the variousparts of my improved scafiold without departing from the-spirit of myinvention: For example the out-rigger used for supporting the sheaves,around which the hoistin cable ofthe'platform passes, and'the brac etsor members to which the ends of the guidecables are attached, may bematerially changed in view of the fact thatthey are dependent to a greatextent upon the facilities convenient at hand in the buildin and at theplace where the scaffold is erecte It is also apparent that while thetriangular frame-work supporting the planks o the platform of myimproved scaffold is pre ferred, yet it may be modified, and alsotherailing or fencing on the outer edge of the platform may be disposedwith or modified without departing from the novel principles involved inmy improvements.

What I claim as newis:

1. A portable scaffold constructed for use on modern high buildings andcom rising a platform, transverse-sills upon w ich the ends of saidplatform rest, u rights medially e rear ends of said sills, andextending both above and below the horizontal plane of the same andformingn per and lower vertical portions which are a out equal in lengthto the width of the platform,

vertically disposed taut flexible guidecablcs arranged fairly close andsubstantially parallel to the plane of the wallof the bulldin overheadoutrigger-s attached to the' buil ing at or near the top thereof,pulleys journaled in the overhanging portions of said Outriggers,hoisting -cables medially encircling said pulleys and having their innerend portions dependin therefrom and in proximity to and para lel withthe guidecables and the outer end portion extending diagonally downwardand outward from said pulleys and secured at their lower ektremitiestothe outer portions of the sills. and suitable winches supported by theinner portions of said sillsto which the lower extremity of the inner.end portions of said hoisting cables are "movably secured, anfljsupporting blocks extending laterally from secured to the rear endsof'said sill s,., -and extending. both above and below theliogie l0.'

' winches siipport'ed by the inner portions of 'theextremities oftheupper-and lower end.-

portions of the uprights and having openings through which the guidecables pass.

' 2. A portable-scaffold constructed for use on modern high buildingsand comprising a v platform, transverse-sills upon which the ends ofsaid platform rest, 'upri ghtsmedi-ally zontal plane of the same andforming upper and lowervertical portions which are about 1 equal inlength to the width of the platform,

vertically disposed taut flexible guide'cables arranged fairly close andsubstantially parallel totheplane of the wall of the building, overheadOutriggers attached to the building at or near the top thereof, pulleysjournaled in the overhanging portions of said outriggers,hoisting-cables medially'encircling said said sills to which the' lowerextremity of the inner end portions of said hoisting- ,cables are.moyably secured, andsupporting blocks extending laterally from theextremi ties of the upper and lower end portions of .the uprights andhaving openings through which the guide-cables pass, and rollers jour-'naled in saidblocks and adapted to contact and rollagainst the outervertical surface of" the building. a v v 3. A portable scafl'oldconstructed for use on modern high buildings and comprising a platform,transverse sills upon which the V endsofs aid platform rest, uprightsmedially secured to the rear ends of said sills, and

extending both above and below the horizonand lower vertical portionswhich are approximately equal inlength to the width the platform,vertically disposed taut fiexible gui egwabQs Qar mged fairly close 'andsubstantiallyparallel *to] the plane of the wall of'the building,overhead outri'ggers at- ,tal plane of the same and forming upper tachedto the building at or near the top thereof, pulleys journaled in theoverhang ing portions of said Outriggers hoisting-ca 'bles mediallyencircling sa-id pulleys and having their inner end portionsdependingtherefrom and in proximity to and parallel with the 'guide-cables andthe outer end por I tions extending diagonally downward and outward fromsaid pulleysand. secured at 4 their lower extremities to the outerportions of'the sills, and-suitable winches supported by the inn'erportions of said sills to which the lower extremity of the 'inner endportions of said hoisting-cables aremovablys'e cured, and supportingblocks extending lat-- erally from the extremities of the upper'ancllower end portions of the uprights and hav-' ing openings through whichthe bles pass, and rollers journaled in said blocks and adapted tocontact and-roll against the outer vertical surface of the building;the..-

blocks being separated approximately, the

vertical length of the uprights andthe lower i extremities of thehoistingcables bein separated approximately. the horizontal wldth, ofthe platform. v

In witness whereof-I have hereuntoset my handthis 23rd day of November,1912.

' JOHN A. GRANGER. I

Witnesses:

FRANK D. Tnoirasom E. K. LUNDY.

